Kerry Butler, 47, was one of a gang of fraudsters led by her brother-in-law, Youth Offending Team boss Peter Nicholson OBE, who claimed wages for workers who didn’t exist.

The mum-of-one swindled almost £80,000 after submitting false time sheets and invoices for two fictitious employees at her job agency, Capability, which provided the council with staff.

Butler, of Leatherbottle Green, Erith, had been cleared of a single count of money laundering last summer, but was found guilty of conspiracy to defraud following a retrial in December 2012.

Sentencing her earlier at Snaresbrook Crown Court, Judge Neil Sanders said: “There was no particular financial pressure on you and this was purely greed.

“Taking all matters into account, I consider this is so serious that only an immediate custodial sentence is appropriate.”

Her brother-in-law, Nicholson, who was responsible for the rehabilitation of young criminals, authorised the payments and arranged luxury holidays at the authority’s expense, the court heard.

The 58-year-old, of Devonshire Road, Bexleyheath, was also involved in a number of other cons and a total of £281,771.90 was stolen between May 20, 2000, and August 31, 2007.

Nicholson was jailed for five and a half years for conspiracy to defraud during the trial last year, while two other men – a finance officer who ran another staffing agency and the boss of a construction firm - were also put behind bars.

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